The flag is additional precaution against data loss. Perhaps in the future the
operation shrink without this flag will be blocked for all formats, but for now
we need to maintain compatibility with raw.
Signed-off-by: NPavel Butsykin <pbutsykin@virtuozzo.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Message-id: 20170918124230.8152-2-pbutsykin@virtuozzo.com
[mreitz: Added a missing space to a warning]
Signed-off-by: NMax Reitz <mreitz@redhat.com>